Common printed circuit board (PCB) construction today uses surface-mount technology (SMT) for mounting surface-mount devices (SMD) to circuit substrates. In SMT, conductive pads are placed on the surface of a printed circuit board, and solder paste is screened onto the pads. A machine then places one or more of the SMT components in their respectively correct places on the PCB, with the terminals of the SMD, in contact with the solder paste, which is usually slightly adhesive. The PCB assembly is then placed in a solder reflow oven, which heats the PCB and the components to a temperature where the solder paste reflows, forming thereby permanent electrical connections between the terminals of the components and the pads of the PCB.
It is this then necessary to remove the excess solder paste, which contains corrosive flux materials, which prevents corrosion of the PCB assembly over time. This process is usually carried out by immersing the PCB assembly in a liquid solder flux removal agent, which is usually water-based.
During the reflow process, the printed circuit board, including integrated circuits, reaches peak temperatures of about 260° C. This hot process step results in a high percentage of the integrated circuits becoming defective, since they are exposed to such high temperatures. One defective integrated circuit on the printed circuit board may result in required rework, or scrapping the complete electronic module. This is in particular a significant drawback for memory modules.
Furthermore, in the course of recent environmental regulations, established soldering processes are being reassessed due to restrictions regarding the use of lead in the soldering process.
It is known to use so-called metallized particle interconnects (MPI), in order to provide an interconnect method for high density board components without using metal pins or solder. The MPI material is formed into tiny micro-columns that align with the contacts of the packaged device and the landing pad contacts of the printed circuit board. When mechanically compressed by a frame holding the integrated circuit, the metallized particles inside the compressed columns join to form a conductive path between the contacts. U.S. Pat. No. 6,325,552, for instance, shows the use of a solderless interconnect for an optical transceiver.
On the other hand, it is known to provide an interconnection device, which has a non-conductive carrier housing and resilient C-shaped interconnecting elements. The interconnection device establishes an electric contact by being disposed between the two components that are to be electrically connected and being subject to a compressing force. An example for such an interconnection device is shown in U.S. Pat. No. 7,186,119 B2.
However, these known interconnecting devices suffer from the disadvantage that their construction is rather time-consuming and costly.